Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0920646 (renal ischemia)
 2,515 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cytosolic NADP+-dependent isocitrate dehydrogenase (IDPc) synthesizes reduced NADP (NADPH), which is an essential cofactor for the generation of reduced glutathione (GSH), the most abundant and important antioxidant in mammalian cells. We investigated the role of IDPc in kidney ischemia-reperfusion (I/R) in mice. The activity and expression of IDPc were highest in the cortex, modest in the outer medulla, and lowest in the inner medulla. NADPH levels were greatest in the cortex. IDPc expression in the S1 and S2 segments of proximal tubules was higher than in the S3 segment, which is much more susceptible to I/R. IDPc protein was also highly expressed in the mitochondrion-rich intercalated cells of the collecting duct. IDPc activity was 10- to 30-fold higher than the activity of glucose-6-phosphate dehydrogenase, another producer of cytosolic NADPH, in various kidney regions. This study identifies that IDPc may be the primary source of NADPH in the kidney. I/R significantly reduced IDPc expression and activity and NADPH production and increased the ratio of oxidized glutathione to total glutathione [GSSG/(GSH+GSSG)], resulting in kidney dysfunction, tubular cell damage, and lipid peroxidation. In LLC-PK(1) cells, upregulation of IDPc by IDPc gene transfer protected the cells against hydrogen peroxide, enhancing NADPH production, inhibiting the increase of GSSG/(GSH+GSSG), and reducing lipid peroxidation. IDPc downregulation by small interference RNA treatment presented results contrasting with the upregulation. In conclusion, these results demonstrate that IDPc is expressed differentially along tubules in patterns that may contribute to differences in susceptibility to injury, is a major enzyme in cytosolic NADPH generation in kidney, and is downregulated with I/R.
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PMID:Role of cytosolic NADP+-dependent isocitrate dehydrogenase in ischemia-reperfusion injury in mouse kidney. 1910 11

Recently, kidney fibrosis following transplantation has become recognized as a main contributor of chronic allograft nephropathy. In transplantation, transient ischemia is an inescapable event. Reactive oxygen species (ROS) play a critical role in ischemia and reperfusion (I/R)-induced acute kidney injury, as well as progression of fibrosis in various diseases such as hypertension, diabetes, and ureteral obstruction. However, a role of ROS/oxidative stress in chronic kidney fibrosis following I/R injury remains to be defined. In this study, we investigated the involvement of ROS/oxidative stress in kidney fibrosis following kidney I/R in mice. Mice were subjected to 30 min of bilateral kidney ischemia followed by reperfusion on day 0 and then administered with either manganese (III) tetrakis(1-methyl-4-pyridyl) porphyrin (MnTMPyP, 5 mg/kg body wt ip), a cell permeable superoxide dismutase (SOD) mimetic, or 0.9% saline (vehicle) beginning at 48 h after I/R for 14 days. I/R significantly increased interstitial extension, collagen deposition, apoptosis of tubular epithelial cells, nitrotyrosine expression, hydrogen peroxide production, and lipid peroxidation and decreased copper-zinc SOD, manganese SOD, and glucose 6-phosphate dehydrogenase activities in the kidneys 16 days after the procedure. MnTMPyP administration minimized these postischemic changes. In addition, MnTMPyP administration significantly attenuated the increases of alpha-smooth muscle actin, PCNA, S100A4, CD68, and heat shock protein 47 expression following I/R. We concluded that kidney fibrosis develops chronically following I/R injury, and this process is associated with the increase of ROS/oxidative stress.
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PMID:Reactive oxygen species/oxidative stress contributes to progression of kidney fibrosis following transient ischemic injury in mice. 1945 20

Ischemic pre-conditioning protects the kidney against subsequent ischemia/reperfusion (I/R). This study investigated the role of cytosolic NADP(+)-dependent isocitrate dehydrogenase (IDH1), a producer of NADPH, in the ischemic pre-conditioning. Mice were pre-conditioned by 30 min of renal ischemia and 8 days of reperfusion. In non-pre-conditioned mice 30 min of ischemia had significantly increased the levels of plasma creatinine, BUN, lipid peroxidation and hydrogen peroxide in kidneys, whereas in pre-conditioned mice, the ischemia did not increase them. The reductions of reduced glutathione and NADPH after I/R were greater in non-pre-conditioned mice than in pre-conditioned mice. Ischemic pre-conditioning prevented the I/R-induced decreases in IDH1 activity and expression, but not in glucose-6-phosphate dehydrogenase activity. In conclusion, protection of the kidney afforded by ischemic pre-conditioning may be associated with increased activity of IDH1 which relates to increased levels of NADPH, increased ratios of GSH/total glutathione, less oxidative stress and less kidney injury induced by subsequent I/R insult.
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PMID:Protective role of cytosolic NADP(+)-dependent isocitrate dehydrogenase, IDH1, in ischemic pre-conditioned kidney in mice. 2150 85